Novel Deep Eutectic Solvents with Different Functional Groups towards Highly Efficient Dissolution of Lignin
Development of effective solvents for lignin is of high importance. Herein, two types of novel deep eutectic solvents (DESs) were designed employing lactic acid and N-methylthiourea as the hydrogen bond donors and four different quaternary ammonium salts as the hydrogen bond acceptors. The designed DESs could efficiently dissolve different types of lignin. Mechanism investigation revealed that the functional groups in the DESs significantly affected their ability to dissolve lignin, and a positive correlation was found between the solubility of lignin and the subtraction value of α and β (Kamlet-Taft empirical parameters).